LONG-TERM DEBT - Components of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Borrowings [Abstract]
Less: Current maturities	$ (3,407)	$ (3,381)
Total Long-term Debt	236,979	238,643
Unamortized debt issuance costs	$ 8,300	$ 10,100
ABL Revolver
Borrowings [Abstract]
Interest rate	4.00%	2.90%
Term Loan B
Borrowings [Abstract]
Interest rate	7.30%	7.10%
Promissory note payable
Borrowings [Abstract]
Interest rate	2.90%	2.90%
Carrying Value
Borrowings [Abstract]
Total Debt	$ 248,716	$ 252,097
Less: Current maturities	(3,407)	(3,381)
Total Long-term Debt	245,309	248,716
Carrying Value \| ABL Revolver
Borrowings [Abstract]
Total Debt	0	0
Carrying Value \| Term Loan B
Borrowings [Abstract]
Total Debt	246,875	249,375
Carrying Value \| Promissory note payable
Borrowings [Abstract]
Total Debt	1,841	2,722
Fair Value
Borrowings [Abstract]
Total Debt	247,790	254,591
Less: Current maturities	(3,398)	(3,406)
Total Long-term Debt	244,392	251,185
Fair Value \| ABL Revolver
Borrowings [Abstract]
Total Debt	0	0
Fair Value \| Term Loan B
Borrowings [Abstract]
Total Debt	245,949	251,869
Fair Value \| Promissory note payable
Borrowings [Abstract]
Total Debt	$ 1,841	$ 2,722

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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